Polyimides (PI), and in particular polyetherimides (PEI), are high performance polymers having a glass transition temperature (Tg) of greater than 180° C. These polymers further have high strength, heat resistance, and modulus, and broad chemical resistance. Polyetherimides are widely used in applications as diverse as automotive, telecommunication, aerospace, electrical/electronics, transportation, food service and healthcare. Adding a reinforcing filler helps provide materials that are particularly useful as molded parts for metal replacement, for example in automotive and electrical/electronic applications since these compositions offer good mechanical and thermal properties.
However, when prepared under certain conditions, polyetherimides can have small amounts of residual phenolic monomers. In some instances these impurities may correspond to the monomeric phenolic starting materials initially used to manufacture the polyetherimide. Besides affecting polymer properties, residual monomers can also be of concern in view of emerging regulatory considerations. Therefore, complete conversion of monomers is usually the desire of any polymer producer but is not always attainable. To that end, there remains a need in the art for thermoplastic polyetherimide compositions whose residual phenolic monomers exhibit certain beneficial characteristics. Desirable characteristics of such residual phenolic monomers include, among others, relatively little or even no estradiol binding activity.